Suddenly immune to vodka

I’m a woman in my 20’s. 5’2- 128lbs I drink a little on the weekends never anything heavy. I’m a big fan of vodka – deep eddies, Absolut and recently new Amsterdam (so smooooth). Maybe some dos Equis or Pacifico’s and last weekend I was feeling good. Yesterday I had some twice baked potatoes and did four shots. I waited and waited, nothing. I did four more and waited and waited, nothing. I’m so disappointed. In the past 8 shots was way more than enough. If I drink heavy it’s every other weekend IF that often. I tried a dos esquis and felt a small buzz. I have trouble sleeping when I drink heavy and I had the same sort of difficulty just didn’t feel it. I was alert, no slurring, able to pass all sobriety tests my friend issued. Tonight I had two fish fillets and threw back a one of those small bottles of don julio 70 black and still nothing. I used to have this condition with my serotonin where on medication I had too much of it which meant fsr that alcohol did not work. It’s so sudden and I’m just beyond disappointed that I may not be able to enjoy vodka anymore. Anyone else have this happen?